1. Field of the Invention
The present invention relates to a carbon component and a method for manufacturing the carbon component.
2. Description of the Related Art
In a CVD system for epitaxially growing silicon or a compound semiconductor wafer, a susceptor has been used for mounting thereon a wafer. A conductive graphite base material has generally been used in the susceptor for generating heat by means of induction heating. Since graphite exhibits low electrical resistance, high heat resistance and chemical stability, it can be preferably used in such a field of CVD system. However, since a process rate is important for epitaxial growth, wafers are exchanged even at a relatively high temperature before an interior of the CVD system is sufficiently cooled, so that the susceptor is exposed to the atmosphere while still remaining heated. Therefore, if the graphite is used for a base material as it is, there will arise a problem of the base material reacting with air, to thus become heavily deteriorated. In a system of using a CVD susceptor for epitaxial growth of gallium nitride, and the like, ammonium is used as a source gas. When decomposed by heat, ammonium produces hydrogen and nitrogen. Although nitrogen is used as a source gas for a gallium nitride film, hydrogen reacts with the graphite at a high temperature, to thus produce a hydrocarbon gas, like methane. Therefore, the graphite is eroded. For this reason, in order to prevent reaction of the atmosphere or hydrogen with graphite, the susceptor made of graphite is coated with ceramic, like SiC (see, for instance, JP-B-4071919 or JP-A-2004-200436). The contents of JP-B-4071919 and JP-A-2004-200436 are incorporated herein by reference.